fix: Use old referral code

This commit was made without the use of generative AI.

Signed-off-by: Jacob Schlecht <dadadah@echoha.us>

README.md

@@ -48,7 +48,7 @@ To get started, find yourself a suitable server to deploy onto, we recommend sta
 >
 > **We've partnered with Hostinger to bring you a 20% discount off VPS hosting!**
 >
-> 👉 https://www.hostinger.com/vps-hosting?REFERRALCODE=stoatchat
+> 👉 https://www.hostinger.com/vps-hosting?REFERRALCODE=REVOLTCHAT
 >
 > We recommend using the _KVM 2_ plan at minimum!\
 > Our testing environment for self-hosted currently sits on a KVM 2 instance, and we are happy to assist with issues.